A: Endomitosis does not cause karyokinesis or cytokinesis.
R: In endomitosis, mitosis occurs within the nucleus.
A: Synaptonemal complex develops between two synapsed homologous chromosomes.
R: Mitosis cannot be completed without the synaptonemal complex.Options~
1. If both Assertion & Reason are true, and the reason is the correct explanation of the assertion.
2. If both Assertion & Reason are true, but the reason is not the correct explanation of the assertion.
3. If the Assertion is a true statement, but Reason is false.
4. If both Assertion and Reason are false statements.
Meiosis can not be completed without the synaptonemal complex.
A: During anaphase-II, chromatids of a chromosome separate.
R: Centromere of a mitotic chromosome divides during anaphase.
A: Dictyotene stage occurs in females only.
R: Gametogenesis rests for a long period at the diplotene stage in females.
A: Each chromosome of bivalent attaches with two spindles in metaphase.
R: In metaphase, bivalents migrate towards the metaphasic plate.
A: G2-phase is a pre-mitotic phase.
R: Chromosomes undergo condensation in this phase.
A: Anaphase-I is the actual phase of reduction in the number of chromosomes.
R: Homologous chromosomes move to the opposite poles with both their chromatids.
A: Golgi bodies and ER disappear in early prophase.
R: Their reorganisation stage is anaphase.
In mitosis, prophase is the longest phase of karyokinesis.In early prophase, nuclear membranes, nucleolus start disintegrating. cells cytoskeleton, Golgi complex, ER, etc disappear.
Their reorganisation occurs in telophase.
A: The complete disintegration of the nuclear envelope marks the start of metaphase.
R: Chromosomes are distinct with two chromatids at this stage.
A: Chiasmata counting stage is diplotene.
R: Dissolution of the synaptonemal complex occurs except at the sites of cross overs.